400 ON THE DRYING UP OF THE RIVERS TEVIOT, NITH, AND CLYDE. 



plete the account of this phenomenon. The frost and gale of wind from the east 

 which produced it, ceased on the forenoon of the 27th November. This change 

 appears to have been brought about by the occurrence of a severe storm, or rather 

 a hurricane, which came from southern latitudes. This is the storm alluded to 

 at the outset of the paper, during which the barometer reached a great depres- 

 sion. In fact there were two storms, one following close upon the other, and 

 which reached the British Islands on the 26th and 28th respectively, moving in a 

 northerly direction. On these days, they descended low enough in the atmosphere 

 to sweep over the surface of our islands. That they had previously affected the 

 upper regions of the atmosphere, is shewn by the fact, that, so early as the night 

 of the 25th, the barometer began to sink all over the British Islands, and, not- 

 withstandhig the prevalence of the frost and easterly gale of the 26th, which are 

 calculated to elevate the mercury, the barometer continued to sink constantly and 

 regularly until the 20th, when the most violent part of the storm occurred. On 

 the 25th and 26th, therefore, it may be assumed, that the higher regions of the 

 earth's atmosphere over this portion of the globe had become loaded with warm 

 vapour brought by the stoim, the upper part of which was in advance of that 

 part sweeping along the surface of the globe ; and hence, on the forenoon of the 

 27th, by which time the storm had approximated to this part of the earth's 

 surface, the temperature suddenly rose, a:nd the easterly gale as suddenly mo- 

 derated. 



Had it not been for the advent of these two storms to this part of the globe, 

 at the exact period now mentioned, our rivers, instead of remaining dry for only 

 twelve or fourteen hom-s, might have continued in that state for a much longer 

 period, to the inconvenience and injury of many thousands of persons, dependent 

 on the flow of their waters for employment and subsistence. 



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